Newer files are copied in both directions. This means if a new version of a file exist on the server, it will get copied (or restored) to the client. Similarly, a new file on the client will get copied (backed up) to the server. Click here for more information.

Files on the server are copied to the client if they are different. This is similar to running a restore operation with one difference: If Delete Files is checked, local files on the client will be deleted if they do not exist on the server.